A laser radar device disclosed by the following patent references 1 measures the shape of an underwater object, and is mounted in a ship, an underwater moving object, or the like.
This laser radar device radiates laser light toward a measurement plane, and also receives the above-mentioned laser light which is reflected by the measurement plane and then returns thereto and measures the elapsed time that elapses from the time of radiating the laser light to the time of receiving laser light which is a reflected wave.
After measuring the elapsed time, this laser radar device calculates the distance from the moving object in which the device in question (laser radar device) is mounted to the measurement plane from the elapsed time, and images the distance.
While this laser radar device uses a one-dimensional array light receiver in order to be able to measure the detailed shape of a measurement plane at a short distance, the laser radar device does not have a function of changing the speed or the altitude of the device in question with respect to the measurement object, as needed, and a function of changing a specification of the laser light which is radiated toward the measurement plane (e.g., the beam divergence, the beam scanning period, the laser beam diameter, or the like) as needed.